LOS ANGELES (Reuters) - For his first journey into a galaxy far, far away, director Christopher Nolan wanted to tether himself to something close to home.
In his daughter, he found inspiration for a lead character in "Interstellar," Nolan's big-budget epic space adventure rooted in intimate family drama.
"I took the decision to change Murphy into a girl, and I think I may well have done that because my oldest child is a daughter," Nolan said of the teen who suffers when her father, played by Matthew McConaughey, leaves for a long, potentially fatal space journey.
"I wanted to have as close a relationship as possible to the emotional journey of the character."
"Interstellar," out in U.S. theaters on Friday, is expected to be one of the year's biggest films at the box office. And Nolan, who has carved out a prestigious movie career with the "Dark Knight" Batman trilogy and "Inception," believes it takes the audience to the furthest realm of space exploration in film.
After Alfonso Cuaron's space thriller "Gravity" drew some criticism from scientists for its implausibility, Nolan pre-empts controversy by saying anyone who demands scientific rigor from the fantastical film is "going to produce their own level of frustration." The film presents theoretical notions of wormholes and bending the rules of time and space.
"We've certainly crossed over into some interesting territory in terms of the science, but we've always done it at the service of the emotional story at the heart of the film."
"Interstellar" is set in a vague distant future where Earth's inhabitants face an agricultural crisis as dust storms threaten mankind's food and ability to breathe.
McConaughey, fresh off his best actor Oscar win, plays the "everyman" Cooper, a former NASA pilot-turned-farmer who is called to an exploration to find a new home for humans on another world in another galaxy.
To do so, Cooper must leave behind his family, especially his precocious teen daughter, played by Mackenzie Foy, with whom he shares a close bond over astrophysics.
"The hero is stereotypically much more considerate than everybody else. And that's fine, that can also be boring," McConaughey said. "I spent a lot of my time trying to really shine a light and understand (Cooper's) faults."
The film reunites previous Nolan collaborators Michael Caine and Anne Hathaway, who play father-daughter astrophysicists, the Brands. It also stars Jessica Chastain as the adult Murphy.
"She's the one who suffered a great loss, her whole world in a way," Chastain said. "She feels lied to and she feels betrayed and she feels abandoned."
"Interstellar," made by Viacom Inc's Paramount Pictures, Time Warner Inc's Warner Bros and Legendary Pictures for $165 million, is projected by BoxOffice.com to open with $72 million.
For Nolan, who was inspired by films such as Stanley Kubrick's 1968 "2001: A Space Odyssey," the sci-fi genre was missing the element of optimism.
"That optimism and hope is essential to the journey that then results in the expedition that they go on to, and that can only be done by people with a great sense of spirit," he said.
(Editing by Mary Milliken and James Dalgleish)